{"action":"Upgrade element-web to 1.8.4-r0 or later.","affected":[{"fixed":"1.8.4-r0","introduced":"0"}],"component":"element-web","cve_ids":[],"ecosystem":"Alpine","ecosystem_qualifier":"Alpine:v3.22","exploited":false,"fixed_versions":["1.8.4-r0"],"id":"tcs_01M6GW9R4SF6PDYJTH6CWMZW4H","modified_at":"2026-11-03T06:32:41.349393348Z","published_at":"2021-09-13T19:15:19.137Z","references":["https://osv.dev/vulnerability/ALPINE-CVE-2021-40823","https://security.alpinelinux.org/vuln/CVE-2021-40823"],"severity":{"label":"medium","score":5.9},"sources":[{"source":"osv","source_id":"ALPINE-CVE-2021-40823#Alpine:v3.22/element-web","url":"https://osv.dev/vulnerability/ALPINE-CVE-2021-40823"}],"summary":"A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryptio"}